1. Field of the Invention
The present invention relates to an inspection device and a producing method of a wired circuit board, to be specific, to an inspection device for inspecting the presence or absence of a foreign object in an insulating cover layer of the wired circuit board and a producing method of the wired circuit board used by the inspection device.
2. Description of Related Art
Conventionally, a wired circuit board such as a suspension board with circuit has included a metal supporting layer, and an insulating base layer, a conductive pattern and an insulating cover layer that are sequentially laminated thereon. In the wired circuit board, after the formation of the insulating cover layer, the presence or absence of a foreign object in the insulating cover layer has been inspected by using an automatic visual inspection (AVI: Automatic Visual Inspection) device that inspects the entire appearance of the wired circuit board.
There has been proposed, for example, as the AVI device, an inspection device which is provided with an upper illumination means, a horizontal illumination means and a microscope is arranged in opposed relation onto a long film carrier tape provided with an insulating film, a wiring pattern formed thereon and a cover lay layer covering the wiring pattern (ref: for example, Japanese Unexamined Patent Publication No. 2007-42956).
In the inspection device, the upper illumination means is formed as a ring light that uses a LED as a light source and applies light to the film carrier tape so that an incident angle thereof with respect to the vertical direction is in the range of 3 to 45 degrees.
On the lower side of the upper illumination means, the horizontal illumination means extends linearly and is formed from a pair of fluorescent lights that are spaced in opposed relation to each other. The horizontal illumination means applies light to the film carrier tape so that an incident angle thereof with respect to the vertical direction is in the range of 45 to 90 degrees.
The light from the above-described upper illumination means and the horizontal illumination means is reflected on the film carrier tape, and the reflected light is read with a microscope, so that the film carrier tape is inspected.